Wick structure



FIG. 1 shows a perspective view of the wick structure;

FIG. 2 shows a front elevation view thereof, with it being understood that the rear elevation view is identical hereto;

FIG. 3 shows a right side elevation view thereof, with it being understood that the left side view is identical hereto; and,

FIG. 4 shows a top plan view thereof with it being understood that the bottom plan view is identical hereto. 

CLAIM The ornamental design for a wick structure, as shown and described. 